Flush closing sliding door assemblies



Jan. 4, 1966 P. KOLLSMAN FLUSH CLOSING SLIDING DOOR ASSEMBLIES 2 Sheets-Sheet 1 Filed March 23, 1964 INVENTOR. Paul Rolls/nan Jan. 4, 1966 v P. KQLLSMAN 3,226,777

FLUSH CLOSING SLIDING DOOR ASSEMBLIES Filed March 25, 1964 2 Sheets-Sheet 2 20 W @mi q 2', I I 15 17 /9 INVENTOR. Paul Kollsman 1y known.

United States Patent This invention relates to improvements in flush closing slide panel doors. This application is a continuation-v in-part of my earlier application Serial No. 172,164, filed February 9, 1962, now abandoned. i

Plush closing sliding panel door assemblies are basical- C In the known assembly individual door panels are urged into flusha-butting position by an arrangement of springs wlhich press against the top and bottom portion of each door panel from the rear and urge the panel in a direction normal to: its plane forward, normally against a lip or stop against which the door panel rests when closed.

The door is opened by pushing one panel back and sliding it behind another, by which action the afore mentioned springs are compressed. t t

The spring fonce must of necessity be sufficient to press the door panels forward into closing position during which action a certain degree of friction is encountered between the end surfaces of the panels which are about to move into abutting position. p

In the position in which the doors are closed the biasing springs which press against the door panels from the rear are in their most extended position. When a door is pushed back the spring is put under increased tension, and a maximum force is exerted by the springs when the springs are fully deflected or compressed in the position in which one panel is behind another. The increased spring tension under this condition is undesirable as it increases the friction between the doors and makes them harder to move.

, Another disadvantage of the known spring arrangement is that the point of application of force against the doors shifts as the doors are being moved from side to side. The ideal force application at which the force bears centrally against the door panel is disturbed when the door panel is slid to one side, whereby the point of force ap plication shifts in the opposite direction, thereby decreasing the biasing effect on the then leading portion of the door'and increasing it onthe trailing portion.

A flush closing sliding door arrangement is commercially acceptable-only if its doors are easily movable by application of a minimum force which, on the other hand, must be sufiicient to move the doors into flush closing position under all conditions of normal service. i

. It is therefore desirable toeliminate excessive or unequal or non-uniform biasing forces by a device which performs its function without excessive spring force and without shifting of the force when the panels are moved. The present invention provides such a device for biasing the top portion of a slidingdoor.

The invention employs a downwardly facing top track for the door panels. The top track is slanted in a direction normal to the plane of the door panels and the slope or slant extends throughout the range ofmoveme-nt of the door panels from side to side. The top track is further wide enough to accommodate two doors in the position in which one door is behind another.

Each door is fitted with a tracking means which bears against the slanted track with. spring force and biases the door toward that position in which the spring element is extended. The anrangementis suoh that for all positions of a door panel slight pressure against the face of the door causes the top portion of the door to move in a rearward direction, whereby the tracking means moves onto a portion of the slanted track in which the relilient spring means is more compressed. As soon as the pressure against the door is released, the door moves forward.

It is known in this connection to mount doors in doubly grooved tracks comprising a forward groove and a rearward groove parallel to the forward groove. Each door panel is fitted with a conventional spring catch for engaging one groove or the other. A forward door panel can thus be rearwardly displaced from its front track groove out of which its spring catches are forces. The spring catches then snap into the rear groove and remain there until the panel is again forcibly derailed to the front. No biasing action is invloved in this known device. I

It is further known to obtain an improved seal both of a stationary as well as of a slidable glass panel by mounting the panel in an oversize track which is wider than the thickness of the panel and in which the panel is urged forward into sealing position with respect to a lip by means of a rearwardly up slanted track bottom on which the panel tends to slide forward towards the lip. No interchange of panels is involved in this construction and notfiush fit between panels is obtained.

.This known panel arrangement is in no Way equivalent to the arrangement of thepresent invention as the results differ in that no interchange of panels and no flusih fit is obtainable by the known contruction. Furthermore, the biasing force obtained in the known device is a function of the weight .of the panel which weight would not be active as a biasing force, if the device is inverted to move the slanted track from the bottom to the top.-

Finally, the present invention is based on the recognition that the biasing force for the upper portion of the door should be slight, as practically little more is in volved than tilting the upright door panels forward by a gentle force. This is all the more important, as forces to open, slide and close doors are customarily applied below the horizontal center line of the door. This is apparent from the conventional installation of conventional door knobsat a point considerably below one-half of the height of the door. For the same reason, the application of forces in the sliding doors should preferably be such that a force applied to the door at the customary height acts principally to displace the door bottom rearwandly, and

only to a minor degree to displace the top of the door at which top portion the applied force should. therefore be slight. t t

The present improvement offers particular advantages if used in connection with a flush closing sliding door assembly disclosed in. the copending application of Saudek and Radanyi, Serial No. 353,701, filed March 23, 1964 in which the panel bottoms rest on a slanted track so as to move into flush closing position by the action of gravity.

.These and various other objects, features and advan- (ages of this invention will appear more fully from the detailed description which follows accompanied by drawings showing, for the purpose of illustration, a preferred embodiment of the invention. The invention also resides in certain new and original features of construction and combination of elements hereinafter set forth and claimed. Although the characteristic features of this invention which arebelieved to be novel will be particularly pointed out in the claims appended hereto, the invention itself, its objects and advantages, and the manner in which it may be carried out,- may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part of it in which: 1 r p FIG. 1 is an elevational end view, partially in section, of a closet door assembly; and

FIG. 2 is an elevational end view,

partially section, of a passage door assembly. 1 t Y In the following description and in the claims various details will be identified by specific names for convenience. The names, however, are intended to be generic in their application. Corresponding reference characters refer to corresponding parts in the several figures of the drawmgs.

The drawings accompanying, and forming part of, this specification disclose certain specific details of construction for the purpose of explanation of broader aspects of the invention, but it is understood that structural details may be modified in various respects without departure from the principles of the invention and that the invention may be incorporated in other structural forms than shown.

A room space A and a closet space B are separated by a flush sliding panel door assembly comprising panels 12 and 13. The door panels are guided into opposite tracks, a sill or bottom track 15 of any desired construction and a top track 16. The tracks may be of stamped, extruded or molded construction of metal or plastic material.

The construction of the sill track assembly is of no importance in considering this invention. Any conventional design may be employed together with means for exerting on the door panels a force which urges the panels forward against a forward lip 25. This force is represented by the arrow F. It is understood, however, that the sill 15 is wide enough to accommodate one door behind another, as shown.

The top track 16 comprises a sloping or slanted door engaging surface 18 imparting to the door panels 12 and 13, in conjunction with other elements in the door panels, a bias towards its forward lip 26. A rearward lip 27 retains the door panels in the opposite direction. The door panels are guided in the top track by suitable antifriction devices. These may be made from metal, or low friction plastics. Tetrafluoroethylene polymer plastic, commonly known as Teflon, is a preferred example of such plastics. These antifriction devices may assume diffe-rent forms.

The drawings show a ball 28 resting in a spherical seat 31 in a socket 29. The socket has a stem 32 on it comprising a flange or shoulder 33. A helical compression spring 34 bears against this shoulder with one end, and the other end of the spring rests on the bottom of a cylindrical sleeve 35 seated in a bore 36 in the panel top. The bore 36 is concentric with a larger bore 36 accommodating the socket 29. Manifestly both bores may be drilled simultaneously with a combination tool.

The stem 32 is centered and guided within the sleeve 35 in a reduced neck 37 of the latter at the top and a hole 38 at the bottom through which the stem 32 extends. The neck portion 37 terminates in an enlarged flange 39 with which the sleeve rests on the bottom of the large diameter bore 36, thus preventing the sleeve from slipping to the bottom of the bore 36.

The spring forces the socketed ball 28 against the slanted surface 18 of the top track as a result of which the door panel tends to move forward to rest against the lip 26.

The door panel 13 which in the drawing is shown behind panel 12 is equipped with similar spring urged top track engaging elements 28, 29 and rests against the panel 12 along low friction spacer strips 40 which also prevent scratch marks from forming on the finished panel surfaces.

The panels rests on the bottom track 15 by suitable antifriction elements 41 whose design is optional, it being understood that means are provided for urging the panels forward as indicated by arrow F.

In operation the door panels assume a flush closing position as the tops of the panels are being urged forward by the action of the spring 34, the element 28 and the slanted surface 18 of the top track which is uniformly sloped across the door opening.

At the bottom the panels are urged forward as indicated by F. The door is opened by pushing one panel back (in the illustrated instance panel 13), in order to slide it behind another panel (in the illustrated instance panel 12). Of course, panel 12 may equally slide behind panel 13.

FIG. 2 illustrates the invention as applied to a passage door comprising three panels 11, 12 and 13 which may be displaced by a person coming from either room space A or room space B.

The construction of the top portions of the panels is identical with that described above. The top track 16 however comprises two slanted surfaces bordered on the outside by panel retaining lips 26 and 27. The slanted surfaces form a generally concave track surface whose most elevated roof portion 42 defines the center position normally assumed by the panels when in flush closing position.

The bottom track 15 is also of generally concave form by reason of two door supporting surfaces 16 which slant downwardly towards a central lowest centering portion 19.

The shape of the outer edges of the track is optional. It may be beveled along both edges as shown at 20. Lips 24 and 25 define the edges of the supporting surface 17.

The V- or U-shaped bottom track arrangement for passage doors forms the subject matter of a copending application of Kollsman, Radanyi and Saudek, Serial No. 353,753, filed March 23, 1964.

The weight of the door panels 11, 12 and 13 imparts to the panel-s a tendency to assume a centered position in line with the centering portion 19 when the panels are slid sideways into position in which they clear the lateral vertical edges of the panels, thus assuming a flush closing position.

The door is opened by pushing a panel back and sliding it behind another panel. Thus panel 11 may be considered as having been moved into the position shown in FIG. 2 by a person walking from B to A and panel 13 by a person walking from A to B.

The slant of the door engaging portions is uniform throughout the length of the track. For this reason the door panels may slide into any position, singly or one behind another, and panel positions may be interchanged at will, so that each panel of a three-panel assembly may assume any one of three positions for closing the door aperture.

What is claimed is:

1. A flush closing sliding door assembly for a structural door opening, the assembly comprising, in combination, a plurality of sliding doors; a common door supporting sill on which the doors are movable with freedom to move from side to side as well as at right angles thereto, said sill having a door supporting upper surface downwardly slanted in a forward direction to impart to the doors under the influence of gravity a bias to move forward, said upper surface being wide enough to permit the doors to assume a position on said slanted surface one behind the other while on said surface; means at the sill for limiting said forward movement to retain the doors on said sill; guide means at the top of the opening, said guide means comprising a member having a downwardly facing engagement surface upwardly slanted throughout the range of movement of the doors from side to side and being wide enough to permit the doors to assume a position one behind the other while engaging said downwardly facing surface by the tracking means hereinafter r6- cited; and tracking means at the top of each door, said tracking means comprising a resilient element for urging the tracking means against said engagement surface, thereby tending to move the top of the door into a position on said downwardly facing engagement surface in which said resilient element is extended.

2. A flush closing sliding door assembly for a structural door opening, the assembly comprising, in combination,

a plurality of sliding doors; a common door supporting sill on which the doors are movable with freedom to move from side to side as well as at right angles thereto, said sill having a door supporting upper surface which is downwardly slanted in a certain assumed direction of passage through the door opening throughout the range of move ment of the doors from side to side to impart to the doors under the influence of gravity a tendency to move towards the lowest position on said slanted surface; means at the sill for limiting said last named movement to retain the doors on said sill; guide means at the top of the opening, said guide means comprising a member having a downwardly facing engaging surface which is upwardly slanted in said certain direction throughout the range of movement of the doors from side to side and being wide enough to permit the doors to assume a position one behind the other while engaging said downwardly facing surface by the tracking means hereinafter recited; and tracking means at the top of each door, said tracking means comprising a resilient element for urging the tracking means against said engagement surface, thereby tending to move the top of the door into a position relatively to said engagement surface in which said resilient element is extended, the direction of slant of the upper surface of the sill being divergent with respect to the slant of the engagement surface of the guide means, thereby imparting to the doors a bias to move in the direction of divergence.

3. A flush closing sliding door assembly for a structural door opening, the assembly comprising, in combination,

a plurality of sliding doors; a door bottom supporting member on which the doors are movable with freedom to move from side to side as well as at right angles thereto to permit one door to assume a position behind another, said member comprising a forward door retaining stop and means for urging said doors forward against said stop; guide means at the top of the opening, said guide means comprising a member having a downwardly facing common engagement surface for said doors, said surface being disposed at a downward slant through the range of movement of the doors from side to side and being wide enough to permit the doors to assume a position one behind the other while engaging said downwardly facing common surface by the tracking means hereinafter recited; and tracking means at the top of each door, said tracking means comprising a resilient element for urging the tracking means against said engagement surface, thereby tending to move the top of the door into a position in which said resilient element is extended, the slant being so oriented as to move the tops of the doors in the same forward direction as the direction of movement of the door bottoms against said stop.

4. A flush closing sliding door assembly for a structural door opening, the assembly comprising, in combination, a plurality of sliding doors; a common door supporting sill comprising an upwardly facing surface on which the doors rest with freedom to move from side to side as well as at right angles thereto, said sill surface being of a width greater than a door thickness and sufficient to support three doors one behind another; means for biasing doors on said sill towards a central position midway with respect to its width; guide means at the top of the opening, said guide means providing a downwardly facing common engaging surface for said doors, which surface throughout the range of movement of the doors from side to side has the shape of an inverted shallow V, as viewed in cross section; and tracking means at the top of each door, said tracking means comprising a member for engaging said last named common engaging surface and a resilient element for urging said member against said downwardly facing engaging surface towards the highest position in the apex of the inverted V surface in which position said resilient element is extended, the spread of said V being greater than the thickness of a door and enough to accommodate the tracking means of three doors disposed in register of which one door engages one leg of the V, a second door engages the other leg of the V, while a third door between the first and second doors engages the apex of the V.

References Cited by the Examiner REINALDO P. MACHADO, Primary Examiner. HARRISON R. MOSELEY, Examiner. 

1. A FLUSH CLOSING SLIDING DOOR ASSEMBLY FOR A STRUCTURAL DOOR OPENING, THE ASSEMBLY COMPRISING, IN COMBINATION, A PLURALITY OF SLIDING DOORS; A COMMON DOOR SUPPORTING SILL ON WHICH THE DOORS ARE MOVABLE WITH FREEDOM TO MOVE FROM SIDE TO SIDE AS WELL AS AT RIGHT ANGLES THERETO, SAID SILL HAVING A DOOR SUPPORTING UPPER SURFACE DOWNWARDLY SLANTED IN A FORWARD DIRECTION TO IMPART TO THE DOORS UNDER THE INFLUENCE OF GRAVITY A BIAS TO MOVE FORWARD, SAID UPPER SURFACE BEING WIDE ENOUGH TO PERMIT THE DOORS TO ASSUME A POSITION ON SAID SLANTED SURFACE ONE BEHIND THE OTHER WHILE ON SAID SURFACE; MEANS AT THE SILL FOR LIMITING SAID FORWARD MOVEMENT TO RETAIN THE DOORS ON SAID SILL; GUIDE MEANS AT THE TOP OF THE OPENING, SAID GUIDE MEANS COMPRISING A MEMBER HAVING A DOWNWARDLY FACING ENGAGEMENT SURFACE UPWARDLY SLANTED THROUGHOUT THE RANGE OF MOVEMENT OF THE DOORS FROM SIDE OF SIDE AND BEING WIDE ENOUGH TO PERMIT THE DOORS TO ASSUME A POSITION ONE BEHIND THE OTHER WHILE ENGAGING SAID DOWNWARDLY FACING SURFACE BY THE TRACKING MEANS HEREINAFTER RECITED; AND TRACKING MEANS AS THE TOP OF EACH DOOR, SAID TRACKING MEANS COMPRISING A RESILIENT ELEMENT FOR URGING THE TRACKING MEANS AGAINST SAID ENGAGEMENT SURFACE IN WHICH SAID RESILIENT ELEMENT IS EXTENDED. 